1 <?xml version="1.0" encoding="utf-8"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3     android:layout_width="fill_parent" 4     android:layout_height="fill_parent" 5     android:orientation="vertical" > 6  7     <TextView 8         android:layout_width="fill_parent" 9         android:layout_height="wrap_content"10         android:text="SeekBar声音控制" />11 12     <SeekBar13         android:id="@+id/seekbar"14         android:layout_width="620px"15         android:layout_height="wrap_content"16         android:max="100"17         android:progress="20"18         android:progressDrawable="@drawable/soundbar"19         android:thumb="@drawable/soundbutton" />20 21     <TextView22         android:id="@+id/txtProgress"23         android:layout_width="fill_parent"24         android:layout_height="wrap_content" />25 26     27     <Button28         android:id="@+id/btnStart"29         android:layout_width="match_parent"30         android:layout_height="wrap_content"31         android:text="播放" >32     </Button>33 34 </LinearLayout>

  1 package com.example.seekbar;  2   3 import java.io.File;  4 import java.io.IOException;  5 import android.app.Activity;  6 import android.content.Context;  7 import android.media.AudioManager;  8 import android.media.MediaPlayer;  9 import android.os.Bundle; 10 import android.os.Environment; 11 import android.util.Log; 12 import android.view.KeyEvent; 13 import android.view.View; 14 import android.view.View.OnClickListener; 15 import android.widget.Button; 16 import android.widget.SeekBar; 17 import android.widget.SeekBar.OnSeekBarChangeListener; 18 import android.widget.TextView; 19  20 public class MainActivity extends Activity implements OnClickListener, 21         OnSeekBarChangeListener { 22     // 定义一个SeekBar和一个TextView 23     private SeekBar seekBar; 24     private TextView textView; 25     private Button btn; 26     private MediaPlayer mMediaPlayer; 27  28     @Override 29     public void onCreate(Bundle savedInstanceState) { 30         super.onCreate(savedInstanceState); 31         setContentView(R.layout.activity_main); 32  33         /** 创建MediaPlayer对象 **/ 34         mMediaPlayer = new MediaPlayer(); 35         initView(); 36     } 37      38     // 初始化 39     private void initView() { 40         textView = (TextView) findViewById(R.id.txtProgress); 41         seekBar = (SeekBar) findViewById(R.id.seekbar); 42         btn = (Button) findViewById(R.id.btnStart); 43         seekBar.setMax(100); 44         seekBar.setOnSeekBarChangeListener(this); 45         btn.setOnClickListener(this); 46     } 47  48     private void play() throws IOException { 49         // 获取文件路径 ,放在SD卡下 50         File audioFile = new File(Environment.getExternalStorageDirectory(), 51                 "welcome.wav"); 52         Log.i("PATH", audioFile.getAbsolutePath()); 53         mMediaPlayer.reset(); 54         mMediaPlayer.setDataSource(audioFile.getAbsolutePath()); 55         mMediaPlayer.prepare(); 56         mMediaPlayer.start(); 57         mMediaPlayer.setVolume(1f, 2f); 58     } 59  60     @Override 61     public boolean onKeyDown(int keyCode, KeyEvent event) { 62         if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN 63                 || keyCode == KeyEvent.KEYCODE_1) { 64             AudioManager audioMa = (AudioManager) MainActivity.this 65                     .getSystemService(Context.AUDIO_SERVICE); 66             audioMa.adjustStreamVolume(AudioManager.STREAM_MUSIC, 67                     AudioManager.ADJUST_LOWER, 68                     AudioManager.FX_FOCUS_NAVIGATION_UP); 69         } else if (keyCode == KeyEvent.KEYCODE_VOLUME_UP 70                 || keyCode == KeyEvent.KEYCODE_2) { 71             AudioManager audioMa = (AudioManager) MainActivity.this 72                     .getSystemService(Context.AUDIO_SERVICE); 73             audioMa.adjustStreamVolume(AudioManager.STREAM_MUSIC, 74                     AudioManager.ADJUST_RAISE, 75                     AudioManager.FX_FOCUS_NAVIGATION_UP); 76         } 77         return true; 78     } 79  80     @Override 81     public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) { 82         int i = seekBar.getProgress(); 83         textView.setText("" + i); 84  85     } 86  87     @Override 88     public void onStartTrackingTouch(SeekBar arg0) { 89         // TODO Auto-generated method stub 90  91     } 92  93     @Override 94     public void onStopTrackingTouch(SeekBar arg0) { 95         int i = seekBar.getProgress(); 96         mMediaPlayer.setVolume(i / 100f, i / 100f); 97  98     } 99 100     @Override101     public void onClick(View v) {102         if (v.getId() == R.id.btnStart) {103             try {104                 mMediaPlayer.prepare();105             } catch (Exception e) {106                 e.printStackTrace();107             }108             try {109                 // 播放音效110                 if (!mMediaPlayer.isPlaying()) {111                     play();112                 } else {113                     mMediaPlayer.stop();114                 }115             } catch (Exception e) {116                 e.printStackTrace();117             }118         }119     }120 }